ObjectiveTo examine the independent and synergistic effects of gestational diabetes mellitus (GDM) and low socioeconomic status (SES) on neurodevelopment and attention-deficit/hyperactivity disorder (ADHD) outcomes.DesignCohort study.SettingFlushing, New York.ParticipantsA total of 212 preschool children as a part of the ongoing cohort study.Main ExposuresGestational diabetes mellitus and low SES.Main Outcome MeasuresPrimary outcomes are ADHD diagnosis based on Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria at age 6 years and several well-validated measures of neurobehavioral outcomes, cognitive functioning, ADHD symptoms, and temperament at age 4 years. Secondary outcomes are parent and teacher reports of behavioral and emotional problems at age 6 years. Neurobehavioral measures in relation to GDM and low SES were examined using generalized estimating equations and multivariate logistic regression analyses.ResultsBoth maternal GDM and low SES were associated with an approximately 2-fold increased risk for ADHD at age 6 years. However, the risk by GDM was greater among lower SES families than among higher SES families. Children exposed to both GDM and low SES demonstrated compromised neurobehavioral functioning, including lower IQ, poorer language, and impoverished behavioral and emotional functioning. A test of additive interaction found that the risk for ADHD increased over 14-fold (P = .006) when children were exposed to both GDM and low SES. Neither children exposed to maternal GDM alone nor those exposed to low SES alone had a notable increased risk for ADHD.ConclusionsMaternal GDM and low SES, especially in combination, heighten the risk for childhood ADHD. Long-term prevention efforts should be directed at mothers with GDM to avoid suboptimal neurobehavioral development and mitigate the risk for ADHD among their offspring.

Significance: Cannabis use is becoming more prevalent, including during developmentally sensitive periods such as pregnancy. Here we find that maternal cannabis use is associated with increased cortisol, anxiety, aggression, and hyperactivity in young children. This corresponded with widespread reductions in immune-related gene expression in the placenta which correlated with anxiety and hyperactivity. Future studies are needed to examine the effects of cannabis on immune function during pregnancy as a potential regulatory mechanism shaping neurobehavioral development.

The study examined the effect of maternal and paternal smoking during pregnancy on the child's inattention and hyperactivity/impulsivity symptoms, and the risk for attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD). Generalized estimating equations, incorporating data from multiple informants (parents and teachers), was used to evaluate levels of ADHD as a function of parental smoking. The risk for ADHD, ODD, and comorbid ADHD and ODD was evaluated using polytomous logistic regression. We found that maternal, but not paternal, smoking was significantly associated with elevated inattention, hyperactivity/impulsivity, and total ADHD symptoms in children. Children of smoking, relative to nonsmoking, mothers had a significant increased risk for comorbid ADHD and ODD and ADHD, but not ODD. Although father's smoking was not associated with an increased risk, as it strongly influenced mothers' smoking, intervention for both parents may be most effective in preventing the pathway to ADHD-related problems in the children.